Technical Abstract:
The production of cultivated peanut, an important agronomic crop throughout the United States and the world, is consistently threatened by various diseases and pests. Although information on the variability of morphological traits associated with disease resistance is plentiful, few molecular markers associated with such resistance have been reported. The identification of such markers would greatly assist peanut geneticists in selecting genotypes to be used in breeding programs. The objective of this work was to use simple sequence repeat (SSR) primers previously reported for peanut to identify a molecular marker associated with resistance to the fungus Sclerotina minor (S. minor) Jagger. Total peanut genomic DNA was extracted from 21 cultivated peanut genotypes and subjected to PCR using different SSR primer pairs. As expected, most primer pairs revealed little or no polymorphism among the genotypes tested. However, one primer pair consistently produced a banding pattern distinctly different for those genotypes with demonstrated resistance to S. minor compared to that generated for genotypes with demonstrated susceptibility. The identification of a potential marker for S. minor resistance in peanut may prove to be extremely useful for screening germplasm collections.